Machine for applying protective coatings to the marginal portions of gramophone discs



Nov. 27, 1956 'r G G. 'rHowl-:MAN 2,771,855

MACHINE FOR PPEYING PROTECTIVE COATINGS TO THE MARGINAL PORTIONS OFGRAMMOPHONE DISCS 1954 2 Sheets-Sheet l si s Nov. 27, 1956 T, G. G.'rHowEMAN 2,771,355

MACHINE FOR APPLYINC PROTECTIVE COATINGS To THE MARGINAL PORTIONS 0FGRAMMOPHONE DISCS Filed March 5, 1954 2 Sheets-Sheet 2 INVENToR. 72'.::ump G. MM 70 /02 y a B L United States Patent O MACHINE FOR APPLYINGPROTECTIVE COAT- INGS TO THE MARGINAL PORTIONS OF GRAM- OPHONE DISCSThorwald Georg Gunnar Thoweman, Stockholm, Sweden Application March 5,1954, Serial N o. 414,405

3 Claims. (Cl. 118-232) This invention relates to a machine for treatinggramophone record discs and more particularly for applying a protectivecoating to Ithe marginal portions of such discs.

The main object of the invention is to provide a miachine capable ofapplying a protective coating to the marginal portions of gramophonerecord discs, said coating serving as a spacer between adjacent discswhen piled or placed in closed side 4to side relationship. The coatingmay, if colored, at the same time serve as indication for the type ofrecording carried by the disc.

Another object of the invention is to provide `a machine of the kinddeiined which is capable of applying the said protective coa-ting in asimple and inexpensive manner in connection with the finishing of theedge portion of -the disc normally carried out by a grinding operation.

A still other object of the invention is to provide a machine capable ofapplying a smooth and lthin protective coating to the marginal portionsof the gramophone record disc, said coating being resilient and havingla surface presenting a high friction against similar surfaces onadjacent discs in for instance record changer mechanism.

A further object of the invent-ion is to provide gripping means forhandling the gramophone record disc and securing it in theabovementioned machine during the finishing process and the followingapplication of `the marginal coating.

A machine embodying the invention is illustrated in the accompanyingdrawings, wherein:

Fig. l is a perspective view of the machine seen from behind,

Fig. 2 -is Ia section of the rotatable support and the gramophone recorddisc secured thereto,

Fig. 3 is a partial front view of the support shown in Fig. 2,

Fig. 4 is a fragmentary view of the roller applying the coating to themarginal portions of the gramophone record disc,

Fig. 5 is an exploded cross-section ofthe support and gripping means forsecuring the gramophone record disc during treatment,

Fig. 6 is an exploded cross-section of a furthermodiiication of the discattachment and handling means of Fig. 4,

Fig. 7 is a cross-section on the line 7-7 in Fig. 6 and Fig. 8 is afrontal View of the support of Fig. 6, the seat member being removed.

Referring now yto Figs. l to 4, the machine comprises a shaft 1supported in bearings 2 and 3 carried by a bracket 4. Intermediate thebearings 2 and 3 a belt pulley is secured to the shaft 1. A belt 6 froma motor (not shown) runs over the pulley 5 and imparts a continuousrotation to the shaft 1. The shaft 1 carries at one end a clamping disc7 coupled to the shaft 1 for being driven thereby. Conveniently theremay be pro- 2,771,855 Patented Nov. 27, 1956 vided a spring actuatedcoupling between the shaft 1 and the disc 7 normally keeping the disc 7out of engagement with the shaft 1 but allowing firm connectiontherebetween when the disc 7 is pressed against the shaft end as will beexplained later on. The clamping disc 7 is preferably covered with asoft coating of felt, rubrber or the like and it has in its center atapering bore 8 for a purpose to be explained in the following.

Turning now to the right end of Fig. 1, 9 designates a second shaftcoaxial to the shaft 1 and rotatably supported in spaced bearings 10 and11 carried by a bracket 12. The shaft 9 is axially slidable in thebearings 10 and 11 and carries between said bearings a sleeve member 13,which is free on the shaft 9 and retained thereon by means of two annuli14 and 1S rigidly fixed to the shaft 9 by screws 16 and 17 respectively.The lowermost portion of the sleeve member 13 has a downward projection18 presenting a plane surface 19 sliding against a rail 20 extendingparallelly to the shaft 9. This will prevent the sleeve member 13 fromtaking part in the rotation of the shaft 9.

The projection 18 or the sleeve member 13 has a shoe 21 to which a Wire22 is secured. This Wire runs lover a right hand pulley 23 supported foridling motion in a bracket 25 on the bracket 12 and a left hand pulley24 similarly supported on the -bracket 12. The left end portion of thewire 22 is connected to a spring loaded pedal 26 and the right endportion of the wire is similarly connected to a second spring loadedpedal 27. By depressing said pedals 26 and 27 alternatively the shaft 9may, through the sleeve member 13 indisplaceably mounted thereon, becaused to move accordingly in either direction -against the spring ofthe unactuated pedal. It should be noted that the said pedal springs arecalibrated to normally keep the shaft 9 in a neutral intermediateposition when none of the pedals is actuated.

The end of the shaft 9 facing the clamping disc 7 on the shaft 1 carriesa supporting disc 29 which is rigidly connected to the shaft 9. On itsback the supporting disc 29 has a tapering, frictional edge 31 which inthe position off the supporting disc shown in Fig. l, where the pedal 27is assumed to be fully depressed, engages a tapering, frictional drivingwheel 32, which is continuously driven by a second motor (not shown) tothe yshaft of which i-t is secured, to impart a relatively slowrota-tion to the supporting disc 29 in comparison to that of the coupleddisc 7. Engagement between the driving wheel 32 and the supporting disc29 only occurs when the pedal 27 is depressed and thus when the pedal 27is released no engagement will occur and the supporting disc will be atrest. Secured to the disc 29 there is a gramophone record disc 33 whichis retained by means of a combined pick-up and connector tool accordingto the invention and gener-ally designated by 34 in Fig. 1.

Before referring to the particular design of the said tool 34 it may bementioned that the machine shown in Fig. 1 is a combined finishing andcoating machine. When a gramophone record disc 33 is secured to thesupporting disc 29 there i-s a considerable distance maintained betweenthe supporting disc 29 and the clamping disc 7. As soon as thegramophone record disc 33 is in position the pedal 26 is depressed sothat the disc 33 is clamped between the clamping disc 7 and thesupporting disc 29 by the displacement of the latter with its shaft 9.The tool 34 is received within the bore 8 of the clamping disc 7 and theclamping disc 7 is pressed into engagement with the rotating shaft 1, sothat the clamped gramophone record disc is set in rapid rotation. Nowthe disc 33 is ground by means of a manually operated grinding toolpressed against ythe periphery of the disc 33 in a conventional manner.When grinding is finished thepedalZis releasedandthepedal 27 depressedcause ing enga-gement between the supporting disc 29 and the drivingwheel 32, so that the disc 33 will be retarded and continue to rotate ata lowy speed, say 50 R. P. M.

When the gramophone recorddisc 33. rotatesat such lower speed a coatingis applied to its marginal portions by means which will be describedlater on, and such coating will not set immediately. Therefore thegramophone record disc just treated cannot be` grasped. at its peripheryand after all it is very unsatisfactory to-handle the discs by the nakedhand. Thus it will be quite necessary to have a particular tool forpicking up and handling the record and particularly for removing it fromthe supporting disc 29. Such av tool should be able to safely grasp therecord and permit securing thereof to the supporting disc 29 and it hasbeen found that the most uncompiicated manner to obtain-a suitable toolfor such purposel is to make use of the central hole of the gramophonerecord disc.

One embodiment of such a tool is illustrated more particularly in Fig.2, where the supporting disc 29 is provided with a central cavity 35'partially covered with a washer 35 fixed by means of screws to the frontface of the supporting disc. Furthermore the'disc 29 has threadedthereinto a central guide pin 38 having two opposed flats 39 and 40 aswill be better seen from Fig. 3 which igure also shows that the washer36 has two opposed notches 41 and 42 on either side of the guide pin.The tool 34 previously referred to comprises a exible bowv ofv steelhaving two shanks 43Aand 44 each having a rigid lip extension 45 and 46respectively sized to permit introduction thereof through the centralhole of a gramophone record disc 33. Both lips 45 and 46 have a prong47' and 48 respectively and the bow 34 has two support plates 49 and Stihaving attached thereto resilient pads 51 and 52 respectively of spongerubber or like'material.

When grasping a record disc the bow Shanks are pressed together so thatthe prongs 47 and 48 may pass through the central hole and then the bowis permitted to expand, so that the prongs will catch the disc 33 andpads 51 and 52 will stabilize it. Then the -grasped disc 33 is lifted tothe supporting disc 29 where the central pin 38 enters through thecentral hole of the disc 33 keeping the bow lips 45 and 46 spaced. Bypressing the bow 34 towards the supporting disc 29 the prongs 47 and 48are caused to'enter through the notches 41 and 42 in the washer 36 andthen the tool is slightly turned so that it will remain secured to thesupporting disc 29 and retain the record disc 33 in proper position fortreatment. When detaching the record from the support the tool is turnedin opposite direction so that the prongs are extracted through thenotches 41 and 42 by expansion of the pads 51` and 52 compressed duringthe attachment, andthe record may easily be removed from the guideV pin38 and put aside. A slight pressure on the bow will release thetool34-from the record disc.

Referring again to Fig. l the means for applying the protective coatingto the marginal portions of the gramophone record disc 33 when thelatter rotates at the lower* speed in` the machine as illustrated inFig. l comprises a guide 53 for a sliding bracket54. This bracket 54comprises two protrudingarms` 55'and' 56 having forkedends 57 carrying adispenser wheel generally designated by 59, which is free to rotateandcarried by a shaft 60. Between the arms 55v and S6 of the slidingbracket 54 there is a:

Attached to the rear end of the guide 53 is a spring pulley 67over whichis coiled a wire 68, theend of which is secured to the sliding bracketS4, so that the latter will` betensioned away from the record disc 33.Extend-- ing from the bracket 54 there is further a rod 69 terminatingin a handle 70, by means of which the dispenser wheel 59 may betemporarily pressed into engagement with the edge of the rotating recorddisc. The dispenser wheel 59 which is also shown in Fig. 4 comprises ahollow body serving as a container for the liquid coating substance tobe appliedl to the record disc. substance isintroduced' inV said hollowbody through a lateral aperture therein closed by a cap or the iike (notshown). Around the. periphery or envelope surface'72` of the hollow bodythe diameter is slightly reduced and there are providedperforations 73leading into the hollow body. The perforated envelope surface. iscovered by a permeable, cushiony annular pad 74 which in turn is wrappedby an annular permeable and flexible screen, preferably having a meshwidth 15-l3 dernier and manufacturedof synthetic lilaments;

By pulling the'handle 70 the dispenser wheel S9`mayy mechanism. Thedispenser wheel 59` only has to` be' pressed against the record discduring one or a few revolu` tions ofthe latter. After having been socoated the recordk disc should be placed away so that the coatinglisallowed" to'set.n

The combinedtool accordingv to the invention may obviouslybe modified inseveral respects and to show this two further embodiments thereof willbe described withA referencefto'Fig.- 5 and Figs. 6 to 8 inclusive.

In Fig. 5 the modifiedtool comprises a foot 71 havingl its bottomcovered with a layer 72 of soft and'resilient` material such as spongerubber. To the foot'is threaded a sleeve 73 carrying a slidable knob 74and enclosing. a pipe 75v having a` point 76 pressed into its frontalvmouth protruding through the foot 71. The pipe has an external ange 77intermediate its ends between which and the foot 71 there is providedv ahelical spring 78.` Between the flange 77 and a free washer79surrounding'the pipe 75- there is a weaker spring 80. Slidinglyarranged within the` pipe 75 is a rod 83 having a cross pin 81 behindthewasher'79 and passingv through longitudinal slots 90 and 91 in the pipe75. The knob 74 is closed by a threaded washer 82'secured'to the slottedend of the pipe 75l The rodv 83 terminatesin a releasingbutton 84. Theopposite endofthe rod 83." has a longitudinalslot 85`for receiving theinner ends of two jointedfjaw members 86' and 87' having each a frontaldetent 88 and S9 respectively protruding through each one slot'in thepipe 75 behind'the point 76 in a resilient'manner.

When grasping a fresh record disc the point'76 is simply pressedthroughthe central hoie of the disc 33"andV the.

detents S8', 89" will 'readily snap out outside the disc` for retainingit on the tool. When securingvthe record'disc 33" and the tool to thesupporting disc 29 of the machine hereinbefore described thelatter mustbe provided with a central hole havinga lining 93 ypreferably threadedthereinto.` It has been found advantageousto provide afunnellike recess9Z`around' this lining93, which will facilitate positioning. The point76 andthe outer end of the pipe '75 is simply pushedk into the lining 93by pressing the knob 74 so that the detents 88 and 89 will snap inbehind the lining 93./

When releasing thedisc 33`andV the tool'from supportingldisc 29`thebutton 84'is pushed whereby the detents The coating Though the coatingA88 and 89 are drawn into the pipe 75 by the forked end of the rod 83.The spring 78 will extract the point 76 out of the lining 93 and thebutton 84 is rapidly released so that the detents 88 and 89 will againcatch the record disc 33 while the point 76 still centers in the lining93. Then the tool with the record disc is removed from the supportingdisc 29 and the record disc 33 may be dropped in suitable place by againpushing the button 84.

With reference to Figs. 6 to 8 numeral 94 designates a turned handlehaving a cover 95 of relatively slippery cloth or the like on its discfacing surface. In the top of the tool there is a push button 96 intowhich is screwed one end of a rod 98 having a square or unroundcrosssection. Around the rod 98 there is provided a spring 97 betweenthe handle 94 and the button 96. The rod 98 is slidable but not turnablein the handle 94 and has an enlarged point 101 projecting from the discfacing surface of the handle. Between the inner side of this point orhead 101 and a bushing 100 iixed to the rod 98 by means of a pin 99 isanchored the outer end of a rubber mantle 104, the rear end of which issecured to the handle 94 by a wire ring 106 and a threaded Washer 10S.The point 101 as better seen in Fig. 7 is provided with two opposite andparallel and transverse slots 102 and 103.

When using the tool of Fig. 6 the supporting disc should, as apparentfrom the left part of Fig. 6, have a central recess 112 for receivingthe point 101 of the tool. Around the recess 112 there is provided asquare block 109 having a central hole inside of which there areprovided two leaf springs 107 and 108 kept in place by two projections110 and 111. In picking up the record disc 33 by means of the recentlydescribed tool the button 96 of the tool is pushed so that the rubbermantle 104 is extended when the point 101 is passed through the centralhole of the record disc 33. Then the button 96 is released causing therubber mantle 104 to form an angular bulge outside the disc 33 as shown.Securing of the disc 33 and the tool to the support 29 is attained bysimply entering the point 101 into the recess 112 and turning the toolso that the leaf springs 107 and 108 will snap into the respective slots102 and 103. Releasing of the tool from the support is again obtained byturning the tool in either direction a quarter of a revolution wherebythe leaf springs will release the point 101 for extraction. The recorddisc is dropped away .by again pressing the button 96. It should bementioned that in this latter case it is important that the support 29has a covering 113 which is soft and frictionally engages the recorddisc to prevent it from freely rotating on the support.

The invention is not limited of course to the embodiment and detailsherein shown and described but may be varied in several respects withinthe scope of the appended claims.

I claim:

l. In a machine for treating gramophone record discs; the combination ofan annular support plate adapted to receive a record disc in closelyabutting relation to one of the radial faces of said plate, means forretaining a record disc against said one face of the support plate, ashaft rigidly connected to said plate and extending axially from theother face of the latter, bearing means having said shaft journaledtherein for rotational and axial movement of the shaft, means forselectively displacing said shaft in the axial direction for moving saidsupport plate between first and second axially spaced apart positions,drive means engageable with said support plate only at said firstposition of the latter to there rotate the support plate at a relativelyslow rotational speed, a rotary dispensing roller adjacent said irstposition of the support plate and movable toward and away from thelatter in the radial plane of the support plate for applying aprotective coating to a record disc held against said support plate atsaid first position, means for displacing said dispensing roller in saidradial plane to engage and release the edge of a record disc, an annulardrive plate rotatably mounted 6 t adjacent said second position of thesupport plate coaxially with the latter to frictionally engage a recorddisc held against said support plate when the latter is moved to saidsecond position, and means rotating said drive plate at a relativelyhigh rotational speed so that a record disc held against said supportplate and frictionally engaged by said drive plate will be rotated bythe latter at a speed suitable for the grinding of the edge and marginalportions of the record disc.

2. In a machine for treating gramophone record discs; the combination ofa rotatable support, means for securing a gramophone record disc to saidsupport concentrically with the axis of rotation thereof, means forimparting rotary motion to said support and hence to the gramophonerecord disc secured thereto, and means for applying a coating to themarginal and edge surfaces of the gramophone record disc, said coatingmeans including a rotatable dispenser roller having its axis of rotationparallel to the axis of the secured gramophone record -disc and beingdisplaceable in the radial plane of the latter and actuator means fortemporarily pressing said roller into engagement with the marginalportions of the gramophone record disc, and roller comprising a hollowbody having a perforated envelope surface, and a permeable, exiblemember surrounding said perforated envelope surface of said hollow bodyand capable of being circumferentially indented by contact with the edgeof the record disc, said hol-low body being adapted to contain a liquidcoating substance capable of penetrating said permeable, flexiblemember, and said means for securing the gramophone record disc to saidsupport comprising a gripping handle including members adapted to enterthe central hole of the gramophone record disc, expandable means forhooking the gramophone record disc to said handle and means for securingthe handle to said support so that, following the application of aliquid coating substance to the edge and marginal portions of the recorddisc, the latter can be removed from said support without requiringhand-ling of the disc.

3. In a machine for treating gramophone record discs; the combination ofa rotatable support movable axially between two operative positions,means for securing a gramophone record disc said support concentricallywith the axis of rotation thereof, means disposed adjacent one of saidoperative positions of said support for applying a coating to themarginal and edge surfaces of a gramophone record disc secured to saidsupport as the latter is rotated at said one operative position thereof,said coating means including a rotatable dispenser roller having itsaxis of rotation parallel to the axis of the secured gramophone recorddisc and being displaceable in the radial plane of the latter at saidone operative position of the `support and actuator means fortemporarily pressing said roller into engagement with the marginalportions of the gramophone record disc, said roller comprising a hollowbody having a perforated envelope surface and a permeable, flexiblemember surrounding said perforated envelope surface of said hollow bodyand capable of being circumferentially indented by contact with the edgeof the record disc, said hollow body being adapted to contain a liquidcoating substance capable of penetrating `said permeable, ilexiblemember, means for imparting rotary motion to said support including arst rotary drive means operative to impart a relatively slow rotation tosaid support suitable for the application of a liquid coating to theedge and marginal portions of a record disc secured on said support whenit is located axially at said one position and a second rotary drivemeans operative to impart a relatively rapid rotation to said supportwhen the latter is disposed at the other of said op erative positionsthereof so that the edge and marginal portions of a record disc on saidsupport may be ground with the latter in said other position, and meansnormally retaining said support axially intermediate said two positions,so that the support is rotationally at rest fonpermitting the mountingof a record disc on, and the 973,356 Kinyon Oct. 18,` 19,10 removal of arecord disc from, said support, and being 1,128,903 Riascher et a1. Feb.16, 1915 operative to selectively displace lsaid support to each of1,868,545 Slonneger July 26, 1932. said'two operative positions.2,074,432 Rollings Mar. 23, 1931 5 2,284,366 Bryant May 26, 1942References Cited in the file of this patent 2,330,411' Dettle. Sept 28;1943 UNITED STATES PATENTS 2,385,653 Rockola Sept. 25, 1945

